HPLC analysis of harringtonine and homoharringtonine in the needles of Cephalotaxus griffithii alkaloid fraction and cytotoxic activity on chronic myelogenous leukaemia K562 cell

Abstract

Harringtonine (HT) and homoharringtonine (HHT) are Cephalotaxus alkaloids with considerable antileukaemic activity. The objectives of this research were to (1) determine the content of HT and HHT present in Cephalotaxus griffithii needles alkaloid fraction (CGAF) and (2) compare the antiproliferative activity of CGAF, with that of HT and HHT on chronic myelogenous leukaemia K562 cell. The concentration of HT and HHT was found to be 122.14 and 16.79 mg/g of CGAF, respectively. Treatment of K562 cells with CGAF, HT and HHT decreased the viable cells in a dose- and time-dependent manner. Interestingly, the maximum cell death was found in CGAF, with IC₅₀ value which was 3- to 4.6-fold lower than those of HT and HHT. Our results indicate that HT content in the needles of C. griffithii is higher than HHT, and alkaloids other than HT and HHT in CGAF are predominantly responsible for K562 cell death.

Keywords::

• Cephalotaxus griffithii
• harringtonine
• homoharringtonine
• leukaemia
• K562

Acknowledgements

This research was financially supported by the Institute of Bioresources and Sustainable Development, Department of Biotechnology, Government of India [grant number PBD-3.3]. The authors would like to express the utmost gratitude to Mr Dia Eraijao who helped in locating the plant material. Our gratitude is extended to Dr B.C. Pal (retired scientist) of Indian Institute of Chemical Biology for the helpful discussion.

Competing interest

The authors declare that they have no competing interests.